Manual diffs

quattrokid · 06-12-10, 10:50 PM

WHY OH WHY did the opportunity to manually lock diffs get binned and replaced with an electronic box that shuts down power and brakes spinning wheels instead of driving the wheels with grip

got the cabrio stuck in Mum's residents carpark tonight in about 10 inches of snow

the UrS4 or the 90 quattro wouldnt have batted an eyelid getting out of there BUT the cab ECU decided a 2k rev limit and flashing dashboard lights was order of the night.
DAM its the first time I had to use a spade to get an Audi moving in snow

no I dont have snow tyres on either and never have had them on Suzi or 90 quattro

AAN 5pot · 06-12-10, 10:53 PM

ESP off.??

quattrokid · 06-12-10, 10:54 PM

hadnt thought of that

last week it was fine in the carpark driving up a slight incline with a bit of sideways drift... but now its fresh snow on ice... our survey says UGH UGH!!!

Bring the 90 quattro back up Clive there's a good chap

AAN 5pot · 06-12-10, 11:04 PM

Turn ESP off. this will turn off abs and allow the wheels to slip and you can rock it out and get it moving.

quattrokid · 06-12-10, 11:06 PM

roll on tmw then and I'll try it again

wide tyres dont help either

urS6 · 07-12-10, 12:05 AM

I burst a front CV joint a few years ago in an S6 just a few miles from home - and found I was stranded! What I hadn't appreciated up until that moment is that Audi's wonderful Torsen diffs, by design, do not allow any torque to go to the side with traction if there is no torque at all on the other side. There must be SOME traction on the slipping side in order for the side with better traction to get a multiple of the torque.

With my old 80q, I would just have locked the centre diff and driven home under rear wheel drive.

That's a decade of progress for you!

I really liked the diff arrangement on my 1984 80q. In spirited driving in slippery conditions, I would always lock the centre diff - it really tightened up the car. When driving in snow, I would lock up both diffs and get up hills that no one else could. Fabulous car! If only it had the 230hp AAN engine that my current cars have ...

Coxy · 07-12-10, 12:06 AM

Should have listened to Pimp and bought Winter tyres!!!!

or learnt to drive properly!!!

20vcqdriver · 07-12-10, 09:16 AM

Quote:

Originally Posted by quattrokid

roll on tmw then and I'll try it again

wide tyres dont help either

Not wrong, I feel safer in the old A4 with 185 winter tyres than I do in the Avant with quattro but 245 summer tyres.

Andy10v · 07-12-10, 10:50 PM

That really annoys me about the torsen drivetrain, it would ideally have the diff preloaded so some torque was always sent either way, as you say a torque multiplier is useless when multiplying by 0.

Never had issues with my qauttros when running narrow tyres, wide tyres are a nightmare in snow, really grateful for the rear diff lock (with the auto disengage disabled

)

You can get the diff to shunt power about if you get stuck, just apply brakes gently, gives resistance and torque is sent. Just like using the handbrake in a rear wheel drive car with an open rear diff.

SteveT63 · 07-12-10, 11:52 PM

Quote:

Originally Posted by urS6

With my old 80q, I would just have locked the centre diff and driven home under rear wheel drive.

That's a decade of progress for you!

I really liked the diff arrangement on my 1984 80q. In spirited driving in slippery
conditions, I would always lock the centre diff - it really tightened up the car. When driving in snow, I would lock up both diffs and get up hills that no one else could. Fabulous car! If only it had the 230hp AAN engine that my current cars have ...

I've had to put up with exactly that
combination for the last ten days!!!!...awesome grip and a soundtrack straight from the Monte Carlo Rally!

06-12-10, 10:54 PM	#3
quattrokid 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Ayrshire Posts: 9,654	hadnt thought of that last week it was fine in the carpark driving up a slight incline with a bit of sideways drift... but now its fresh snow on ice... our survey says UGH UGH!!! Bring the 90 quattro back up Clive there's a good chap __________________ RS4 B5 (wife's / ours now ) S3 8L Imola Yellow S3 8L Nogaro blue UrWR SOLD UrS4 saloon (SOLD again) S4 Cabrio (SOLD) A4 cabrio 2.5 V6tdi (SOLD) 80 cabrio 2.6 V6 SOLD 90 quattro 10v SOLD 100 2.2e SOLD FOUNDING MEMBER the 200,000 Plus miles Club

06-12-10, 11:06 PM	#5
quattrokid 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Ayrshire Posts: 9,654	roll on tmw then and I'll try it again wide tyres dont help either __________________ RS4 B5 (wife's / ours now ) S3 8L Imola Yellow S3 8L Nogaro blue UrWR SOLD UrS4 saloon (SOLD again) S4 Cabrio (SOLD) A4 cabrio 2.5 V6tdi (SOLD) 80 cabrio 2.6 V6 SOLD 90 quattro 10v SOLD 100 2.2e SOLD FOUNDING MEMBER the 200,000 Plus miles Club

07-12-10, 10:50 PM	#9
Andy10v Grown up member Classic Audi Club Member Join Date: Dec 2008 Location: Stirling Posts: 861	That really annoys me about the torsen drivetrain, it would ideally have the diff preloaded so some torque was always sent either way, as you say a torque multiplier is useless when multiplying by 0. Never had issues with my qauttros when running narrow tyres, wide tyres are a nightmare in snow, really grateful for the rear diff lock (with the auto disengage disabled ) You can get the diff to shunt power about if you get stuck, just apply brakes gently, gives resistance and torque is sent. Just like using the handbrake in a rear wheel drive car with an open rear diff. __________________ 2005 350z GT Sold-1992 3B S2 coupe-RS2+, 996s, konis, forged rods, rear torsen.... Sold-1993 ABY coupe

06-12-10, 10:53 PM	#2
AAN 5pot Grown up member Join Date: Feb 2010 Posts: 683	ESP off.??

06-12-10, 11:04 PM	#4
AAN 5pot Grown up member Join Date: Feb 2010 Posts: 683	Turn ESP off. this will turn off abs and allow the wheels to slip and you can rock it out and get it moving.

07-12-10, 12:05 AM	#6
urS6 Grown up member Join Date: May 2010 Location: Worcestershire Posts: 115	I burst a front CV joint a few years ago in an S6 just a few miles from home - and found I was stranded! What I hadn't appreciated up until that moment is that Audi's wonderful Torsen diffs, by design, do not allow any torque to go to the side with traction if there is no torque at all on the other side. There must be SOME traction on the slipping side in order for the side with better traction to get a multiple of the torque. With my old 80q, I would just have locked the centre diff and driven home under rear wheel drive. That's a decade of progress for you! I really liked the diff arrangement on my 1984 80q. In spirited driving in slippery conditions, I would always lock the centre diff - it really tightened up the car. When driving in snow, I would lock up both diffs and get up hills that no one else could. Fabulous car! If only it had the 230hp AAN engine that my current cars have ...

07-12-10, 12:06 AM	#7
Coxy 4 Ring Mafia Classic Audi Club Member Join Date: Jul 2007 Location: on the side of a hill in Shropshire! Posts: 28,215	Should have listened to Pimp and bought Winter tyres!!!! or learnt to drive properly!!!